Steam boiler



April 26, 1932. D. s. JAcoBUs STEAM BOILER Filed June 2l, 1920 8 Sheets-Sheet l BY ,W

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8 Shets-Sheet 2 D. S, JACOBUS STEAM BOILER Filed June 21.

April 26, 1932.

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Filed June 21. 1920 8 Sheets-Sheet 3 IN VEN TOR.

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April 26, 1932. D. s. JAcoBus STEAM BOILER Filed June l21. 1920 B Sheets-Sheet 4 INVENTOR. MS2( BY a' I ATTORNEYS. Y

Aprilzs, 1932. D SJACOBUS 1,855,116

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April 26, 1932. D. s. JAcoBus STEAM BOILER Filed June 2l 1920 8 Sheets-Sheet 6 BY www April 26, 1932. D. s. JAcoBUs STEAM BOILER Filed June 2l. 1920 8 Sheets-Sheet 7 INVENTOR.

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April 26, 1932. D. s. JAcoBUs STEAM BOILER Filed June 2l. 1920 8 Sheets-Sheet 8 INVENTOR.

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Patented Apr. 26, 1933 n sra'ras PTiF- Price f DAVID s. JACoEUs, or JERSEY CITY, NEW JERSEY, AssrciNeny To THE EaBCCx a. f

Witcox COMPANY, CE EAYQNNE, NEW JERSEY, a CORPORATION or NEW JERSEY STEAM BOILEE Application filed June '21,

. ed for direct firing; Fig. 4t illustrates diagrammatically the arrangement of the tubes of the upper bank of the supplemental circulatory system of the arrangement shown in Fig. 3; Fig. 5 is a view similar' to Fig. 4 illustrati ng the arrangement of the tubes of the lower bank of the supplemental system of the arrangement shown in Fig. 3; Fig. 6 is a sectional vieW taken on the line 6-6 of Fig. 3; Fig. 7 is a sectional plan view taken onthe. line '1"#7 of Fig. 3; Fig. 7a is a detail sectional view illustrating the lower ends of the economizer tubes Fig. 8 is a longitudinal sectional view of another form of boiler embodying my invention adapted-for Waste heat Work;` Fig. 9 is a section taken through Fig. 8; Fig. 1() is an end view of the boiler shown in Fig. 8; Fig. 11 is a longitudinal sectional view of a modified form of steam boiler for Waste heat Work embodying my invention, Fig. 12 is a sectional elevation taken on the line 12-12 l. of Fig. 11, and Fig. 13 is an end view of the transverse diaphragm or partition of the lower mud drum.

Referring, now, to the drawings, and first to Figs. 1 and 2, 10 is an uppersteam and Water drum, and 11 and 12 two lower aligned mud drums connected to the steam and Waterdrum by banks of boiler tubes 13 and economizer tubes 1a, respectively, the tubes being arranged in staggered rows longitudinally of the boiler and in straight roWs transversely thereof, the tubes being bent at their ends where they enter the drums. The tubes are arranged, longitudinally of the drums, in groups, preferably of two, Which are spaced apart to afford access for removal and re- 1920. Serial No. 390,358.

newal of the tubes and for adjustment of the Scrapers, When used, which are shown. in Figs. 3, 9 and 10, but which may be used on any of the forms of boilers illustrated, including Athe one under consideration. Ordinarily, howfever, the tubes Would be cleaned by rotary soot blowing elements 15, the rotating meansi and intake for which are indicated atl 16. The waste heat gases-such,-,forexample, as may be obtained in the manufacture of zinc', and carrying zinc oXide dust-are conducted to the `boiler by a fluel18, which directs the gases over the tubes 13 and 14. Some of the tubes, preferably near the tubes against whichl the gasesfirst mpinge, may be superheater tubes, as in Fig. 8. FromA the boiler tubes `13- the gases pass vover the economizer tubes 14.-,l the gases being carried from the boiler by the outlet llue19, the side Walls 2O of they setting conning the gases to the tubes during their passage thereover. VThe feed Water inlet 21 is connected to the mud drum 12 of the economizer,which, in kFigs.1 land 2, .is shown separate from the mud drum 11. By placing the dry pipe and steam outlet 17 at the rear end, With respect to the flow of gases, of the-steam'A and Water drum, steam of a maximum degree of dryness isobtained, as the Water in the drum is in the most quiescent state and atthe lowermost level at this point. Beneath the lower Vdrums 11 and 12 are arranged pockets having hopper-shaped tops, whichy are pro-- vided for the reception of zinc oxide or other deposit Which may collect o n thetubesand Which maybe removed by the Scrapers, or the steam soot blowing elements, or in any def sired manner.

In Figs. 3, 4, 5, 6 and 7 I have illust-rated l my invention embodied in asteam boiler of the direct-fired type. The feed Water inlet 21?. is connected to the mud drum 12EL ofthe economizer. The mud drum .12FL may ber separate from the mud drum 11a of the boiler, as in Figs. 1 and 11, or it may be a continua'- tion of the mud drum 11 and separatedthere rfrom by a partitionL 22, as shown in Figs. 3t and 7. In the form here shown,'the-mud1 drum'12a is formed as a continuation ofthe mud drum 11a, and is separated therefromby a partition 22, as shown iny Figs.V 3 and 7.

The drum 10 is connected to the drums 11a and 12a by banks of tubes 13L and 14a, respectively.V The partition 22 may be provided with a manhole or manholes 23 or other openings,`as shown'in Fig. 13. Theopening orA 22 with the opening or openings therein pro`V vides a means of connecting the economizer with the general circulation of r[the boiler, thereby converting the -economizer section to a boiler section. In some instances feed water'fwill cause' corrosion in economizer elements and not in the boiler. Should this be the case, the feature of converting the economizer tubes to boiler tubes is a most useful one, as the economizer can be converted and made part of the boiler and the corrosion thereby overcome until such a time that the feed watercan be treated so as to make it suitable for use in an economizer. The manhole openings 23 inthe partition 22 serve a further useful purpose in providing access from the economizer drum to the boiler drum or vice versa. In some instances, it is desirable to dispense with a manhole at the furnace or hottest end of the boiler mud drum 11, and

when this is done` the boiler muddrum mayV be' entered through the manhole openings 23. By providing the partition with a pluralityT of openings vhaving removable covers the communication between the two chambers may be varied according to the number of covers removed. K

Ferrules 24 or other forms of retarders may be placed in the lowermost ends of the economizer tubes in any of the economizers, as shown in Fig. 7 a, in order to divide the water more evenly between the different tubes than it would be divided without the use of such retarding means. The ferrules or retarders serve to prevent a general circulation being started up within the economizer that would carry some of the ho,t water from the upper steam and water drum downward to the lower economizer drum.

, The steam boiler is provided with a stoker 25, which is here illustrated as of the underfeedtype, al combustion chamber 26 being formed between the front wall 27 and the rea-r wall28, the latter preferably being provided with openings 29 which afford access to 'the dumping plates of the stoker and to the fuel bed, the rear wall preferably being inclined, as indicated. In Vthe form of invention here shown, a supplemental cir-Y culatory system is interposed between thc furnace and the boiler tubes, comprising` a lower Vbank of tubes 30 and an upper bank of tubes 31 connected at their front ends t0 tion chamber.

a common chamber, which is here shown as formed by a drum 32 arranged above and in front of the front wall 27 of the furnace, the tubes 30 and 31 being arrange-d at an angle, as shown, and forming a secondary combusticn Achamber 33 for the furnace gases. A roof bafde 34 of any desired length may be used above and at the rear of the lower bank of tubes 30, and extends forwardly from the rear furnace wall 2S, as shown, and directs the gases forwardly to the secondary combustion chamber. Each bank of tubes 30 and 31 preferably comprise two rows in order that there may be enough cooling effect to prevent overheating of the furnace walls, whereas they will not cool the gases which enter the secondary combustion chamber below a, temperature suitable for securing complete combustion in the secondary 'combus The tubes of the lower bank are arranged one above the other as indicated in F ig. 5, while those of the upper bank are staggered as indicated in Fig. 4. The otherends-of the banks of .tubes 30 and 31 areV connected to drums 35 and 36, respective` ly, the drumy 35 being disposed at the rear of the furnace wall 2S, as shown. A dry pipe 17 is located above the tubes of the economizer as in Figs. 1 and 2. The drum 35 is connected to the mud drum llfL by water tubes 37, while the upper drum 36 is connected to the steam and water drum 10 by water tubes 38. The drum 36 is also connected to the steam and water drum 10 by steam pipes 39. The furnace, which is of the same width, or substantially the same width, as the secondary combustion chamber, is wider than the portion of the flue in which the tubes are arranged, as best shown in Fig. 7. The side walls 40, forming the flue inlet, in which the tubes are disposed, are flared outwardly, at 4:1 (see Fig. 7), and the tubes are arranged substantiallyY to fill the flue transversely thereof so that the boiler tubes 13a against which the Gases from the C P! furnace first impinge are disposed in a wider space and are further spaced apart than are the remaining tubes. In an ordinary boiler, where the tube spacing between the tubes and the'tube lengths are uniform throughout the length of the boiler, the. velocity of the gases is much lower on passing over the last tubes than it is on passing over the first tubes, on account of the increase in density of the gases as they decrease in temperature. In accordance with my invention, the flue and boiler tubes are so arranged that the area for the passage of the gases at the successive rows of tubes in the first portion of the boiler decreases by decreasing the width of the fiue and of the spaces between the tubes, and in this manner I obtain a gradually decreasing flow area so as to maintain a velocity of the gases over the tube surface, which leads to the best results. By making the furnace and icc Lasagne the supplemental circulatory system `wider than the major portion of the flueiin-whiohithe tubes 13a and 14EL are located,a `furnace and a secondary combustion chamber of ample proportions for the thorough combustion of the gases are provided.

'Inclining therear wall 28 in the ,manner indicated, when combined with thev roof'batiie 34, is particularly adaptableto'an underteed Stoker where excess air, under certainfeonditions of operation, passes Ifrom therearpart of the Stoker `mechanism, and through :the dumping plates, and isprojectedirearwardly into the furnace. The -torm o-f'the tuyresiof thek stoker, which admit thefcompressedfair, causes the air to bei-:projected re'arwardly,fand whe-nthe `rear portion of the `tire becomes thin, or whena portion ot the iire iis ybroken through by the action oi the blast, the .construction of the tuyeres .issuch as to project the air and gasesrearwardly. .It 'canfreadily be seen that where a stolrer produces-such an action, the tormot furnace is particularly adapted to give increased ei'cieney,rpartie ularly in combination withV a secondary cornbustion chamber of the characterdescri'bed 'and with a boiler ofthetypehereillustrated.

In Figs. 8, 9 and 10 I have shown `my 1inyention embodied in a modified ,forni otwaste heat boiler. A single mud drum 42 isiconnected to the steam and water drum l by tubes 43, the waste'heat gases being admitted to the boiler through the inlet flue-44, and, after passing over the tubes, leave `by the Outlet flue 45. A plurality ofespaced baiiie plates 431extend upwardly from the bottoni ot the space beneath t le mud drum @between the lower ends otthe tubes 43 suiiicientlyto prevent the gases from being short'circuited around the tubes through the spacebeneath the tubes. These baffles, vof course, closely surround the mud drum 42. The steam is collec-ted by a dry pipe 46 disposed latthe rear end of the boiler, fromwhich thesteam passes to the outlet pipe 47, which is connected to the lower header 4S vofasuperh'eaeter7 trom which the steam passes through the superheater tubes 49 to the upper header 50, the superheater tubes in this form beingdi'sposed between. the boiler tubes, and the header-sheing arranged transversely of the drumsand supported in the setting, asshown. Theheader is provided with a steamwoutlet 51,:as best shown in Fig. 9. I have hereillu'stra'ted Scrapers o2* for removing Zinc oxide'or other deposit trointhe tubes, although, as previousL ly stated, the scrapers `may-be usedfin th eV other forms ot boilers illustrated. `The Scrapers are mounted onerose-heads 53,*which1may'be operated by chains 54'passing over pulleys ene set ot Scrapers being balanced againstthe other ina known manner, and-the chain Jfor the set of Scrapers at one end being attached to counterweights 56.

In the boilers shown in Figs. lrto ,10,in-

elusive, the gases :make apsingle pass `transversely of .the boiler tubes, :thereby veliminating'athedraft resistanceduev to changes i-nithe direction offlow'otthe gases whichoceur ain boilers provided'wiith battles. Theftubes are so proportionedandspacedthat theiflow area overt-hei tubes, between and. around the tubes, incombination withthe staggered .arrangement :of the'tubes, Agives -a .high lratez of heat transfer :from ythe hot gases to the tubes. A maximum heat transfer is 'ithereby secured, with a minimum draft resistance, and thefarrangement :is particularly adaptable J'or'securing Ehigh eicienc-ies.

In Figs. vl1 and 12 I have illustrated another form olsteam boileradapted for waste'heat work, and in whichparts arranged similar'to those of 'the previouslydescribed iigures are similarly numbered, but where baiiies arev used to give 'a longitudinal flowot the lgases along the tubes. The gases.enterthe boiler by two fines 57 controlled by gates 58. In'thisform of my invention, the boilertubes 'and economilzertubes-arebent outwardly: away romthe center line passing through the two drums,

A'ist near one end ot the tubes (as hereshown, the

lower ends :of the tubes), so that .the two banks of tubes on either side of r'the center line are spaced apart .in the mannershown in Fig. l2, the direction oftubes .from the bent portions being inclined toithecenter line.v In

the yfornrhere shown,the"boiler tubes are-separated into definite sections .13", 13C .and 13d by baiiies or walls 59 and 60 extending transversely-of the drums, the baffle or baies 59 extending upwardly from thefoundation wall 61, while the batlie for baiiies 60 are suspended beneath the steam and water drum 10. 'A wall '62 is disposed between :the rboiler tubes 13d and the reconomizer tubes 14a. Alternate baiies or vwalls59 and 62 are provided with central openings 63y and 64,'respectively, at the stop, while the alternate balile or baiiies SOare provided at their lower'ends with two openings 65 on either side of the ,center line, these vopenings-'being approximately .in alignment with they i'lues 57. Thegases .entering through the fluesv 57, therefore, are directed against the bent portions of ythe ftwobanks of tubes, and'theniflow longitudinal-ly ofthe tubesbetweenthebatlie 59` andtheend wall of the setting,-passing through the central opening 63 lof the baiie 59. Thefgases then flow along the tubes of the second bank, and through the two openings65 otthebaiiiefGO. and, in a similar manner, over the remaiuin tubes, `until they pass to the outlet166,:froin which the gases are drawn to the stack bya fan 67. Thegases thus pass from .theinlet dues to the bent endsfof thetubes where they are widened, and lthence longitudinally yot'the tubes to the single'opening 63 in the baiiie 59, and so on through theboiler, the gases passing serially Vover the lbanks of tubes delimited by the battles, and, in general,'flowingvlongitudie nally along the various banks of tubes. In the arrangement shown in Fig. 171, the steam and water drum is extended toward the rear and the dry pipe made to come in the part of the steam and water drum so extended. By employing this construction, the steam is taken from above water which is in a. more quiescent state than should it be taken at a nearer point to the front end of the drum, and the advantage of obtaining steam of the maximum dryness is thereby secured.

Vhat I claim and desire to secure by Letters Patent of the United States is:

l. In a steam boiler,`an upper steam and water drum, two substantially aligned lower water chambers, a feed-water connection to first of said water chambers, econo-inizer tubes connecting said lirst feed-water chamber to the upper steam and water drum, boiler tubes connecting the other water chamber to the steamand water drum, a furnace, and a supplemental circulatory system interposed between said furnace and said tubes, and comprisingtwo banks of tubes connected at one end to a common chamber, the other ends of said two banks of tubes being connected to said steam and water drum and to the sec-V ond-mentioned water chamber, said tubes forming a secondary combustion chamber.

2. In a steam boiler, an upper steam and water drum, a lower mud drum substantially parallelthereto, and tubes having their ends entering and connected to said drums, a flue in which the tubes are located for directing the gases over said tubes in a single, unobstructed pass, the tubes being arranged in rows transversely of the boiler, the portion of the flue enclosing the boiler tubes against which the Agases first impinge being wider in a horizontal plane than the remainder of the flue, and the tubes therein being further spaced apart than are the tubes` in the remainder of the flue the tubes substantially filling the portion or the flue inwhich they are located.

3. In a steam boiler, an unobstructed upper steam and water drum, twolower mud drums, the one formed as a continuation of the other and separated by a transverse partition provided with an. opening, `a removable cover for closingsaid opening, tubes connecting the respective drums to the steam and Water drum, the gases flowing over said tubes in a single pass, and means for introducing feed water to one of said mud drums.

4. In a steam boiler, an upper steam and water drum, a lower mud drum provided with a partition arranged transversely of the drum forming two chambers therein, banks of water tubes and of economizer tubes connecting said upper steam and water drum to the respective chambers of said lower drum, the gases flowing over said tubes in a single pass, means for introducing feed water to one of said drtuns, said partition being provided' with an opening, and mea-ns for closing said opening, whereby the economizer tubes may be operated separately from or as a part of the general boiler circulation at will.

5. In a steam boiler, a steam and water drum set parallel to the general direction of the flow of the furnace gases over the boiler tubes, boiler tubes connected to one end of said drum, an economizer section comprising tubes connected to the other end of said steam and water drum and through which the water flows to said drum the gases flowing in succession over said boiler tubes and then over said economizer tubes, a steam outlet connected to said drum near the rear end thereof with respect to the flow of gases, and a dry pipe connected to said steam outlet and eX- tending towards the rear end of the drum with respect to the flow of gases.

6. In an economizer, upper and lower chambers, means for introducing feed water to the lower chamber, a bank of economizer tubes connecting the upper and lower chambers, said tubes being provided with restrictions for preventing a reverse circulation in any of said tubes. y

7.v In an economizer, upper and lower chambers, means for introducing feed water tothe lower chamber, a bank of economizer tubes connecting the upper and lower cham-Y bers, said tubes being provided with ferrules for preventing a reverse circulation in any of said tubes.

8. In an economizer, upper and lower chambers, means for introducing feed water to the lower chamber, a bank of economizer tubes connecting the upper and lower chambers, said tubes being provided at their lower ends with ferrules for preventing a reverse circulation in any of said tubes.

9. In a steam boiler, an upper steam and water drum, two lower water chambers, lbanks of economizer and boiler tubes connecting the respective Water chambers to said upper steam and water drum, means for introducing feed water to one of said chambers, the tubes connected to the last-named chamber being provided with ferrules whereby a reverse circulation inany of the economizer tubes is prevented.

10. In a steam boiler, an' upper steam and water drum, two lower substantially aligned water chambers, banks of economizer and boiler tubes connecting the respective lower water chambers to said upper steam and water drum, means for introducing feed water to the water chamber to which the economizer tubes are connected, said economizer tubes being provided with ferrules whereby a reverse circulation in any of the economizer tubes is prevented.

l1. In a steam boiler, upper and lower water chambers connected by water tubes, a flue in which the tubes are locatedfor directing the gases over said tubes longitudinally 12. In a steam boiler, upper and lower` water chambers connected by water tubes, a

iue in which the tubes are located for dir-ect ing the gases over said tubes longitudinally of the boiler in a single pass, a space being provided below the watertubes, and a, plurality of baffles extending upwardly trans versely of the flow of gases and across said space, the upper ends of said balil-es extending between the water tubes to prevent sub-V` stantial short circuiting of the gases through said space.

13. In a steam boiler, an upper steam and water drum, two substantially aligned lower water chambers, a feed water connection to one of said water chambers, economizer tubes connecting the feed water chamber te the upper steam and water drum, boilerv tubes connecting the other water chamber to the steam and water drum, a furnace, a supplemental circulatory system interposed between said furnace and said tubes and comprising two banks of tubes connected at one end to a common chamber, the other ends of said two banks of tubes being connected-to said steam and water drum and to the secondmentioned water chamber, said tubes formh ing a secondary combustion chamber, and a dry pipe for the steam located in the upper portion of the steam and water drum abcve the economizer tubes.

14C. In a steam boiler, an upper steam and water drum, a lower mud drum, tubes connecting said steam and water drum to said mud drum, a furnace, and a supplemental circulatory system interposed between said furnace and said tubes, and comprising two banks of tubes connected at one end to a common chamber, the other ends of the tubes being connected to the lower and upper drums, respectively, said tubesrforlning a secondary combustion chamber, and the lower bank of tubes comprising two rows arranged one above the other.

15. In a steam boiler, an upper steam and water drum, a lower mud drum, tubes connecting said steam and water drum to said mud drum, a furnace, and a supplemental circulatory system interposed between said furnace and said tubes, and comprising two banks of tubes connected at one end to a common chamber, the other ends of the tubes being connected to the lower and upper drums, respectively, said tubes forming a secondary combustion chamber, and the lower bank of tubes comprising two rows arranged one above the other, the number and arrangement of the tubes in said circulatory system being such that they exert suliicient cooling effect uponthe gases to prevent'overheatingI ofthe furnacel walls and at the Sametime perlnit'the gases to enter the secondary coii'1 bustion chamber formed between thetubes ro'f' said circulatory system at a temperaturesuf-f vficiently high for securingcomplete combustionfof the gases in saidsecondary combusl tionchamber.

16. In steam boiler, an upper-fst'eam'and water drum, a lower mud drum, tub'esfcon-4 necting saidsteani and waterv drum and saidinnd drum, a furnace, a supplemental lcircuiatcry system comprising an upper and a lower bank of tubes located in advanceof` said iirstnientioned tubes with respect to ther flow of gases and connected aton'e'end-toaA common water chamber and extending in diff ferentdirections to form a secondaryL com` bust-ion chamber, the other ends ofthe EtubesL of saidbank's being connected at theirotlier ends to Ysaid steam Vand water drum andltoy said mud drum, respectively, `the gases: flowing from saidfurnace over' the ,tubesof oneof said banks int-o ysaid secondary combustion chamber andthence over theftubesfcon'-v necting said steamfand water drum tosaid-v mud drum. f

17. In a steam boiler,y an upper steam fand water drum, a lower mud -drum,tub'e's"conl nectingsaid steam and water drum-and said mud drum, a furnace, asupplementalcircwlatory system comprisingfanr upper and a*A lower bank of tubesylocate'd inl advance of:

said first mentioned tubes with respect'- to the flow of gases and connected at one end tol a common water chamber 'and extendingl in: differentgdirections to form a secondary' com bustion chamber, the otherends ofthe tubes of said'banks being coiinected'at their otheri4 ends 'to said steam and watendrumiandt' said mud drum, respectively, thegases {iowing fromsaid furnacel over the tubes of one of said banks into said :secondarycombustiom chamber and thence over the tubes connecting?.

said steam and water drum to said mud drum, and a roof baffle disposed'above the lower bank of tubes and extending forwardly from the furnace wall for directing the gases to said secondary combustion chamber.

18. In a steam boiler, an upper steam and water drum, a lower mud drum, tubes connecting said steam and water drum and said mud drum, a furnace, a supplemental circulatory system comprising an upper and a lower bank of tubes located in advance of said first mentioned tubes with respect to the flow of gases and connected at one end to a common water chamber and extending in different directions to forni a secondary coinbustionchamber, the other ends of the tubes of said banks being connected at their other ends to said steam and water drum and to said "las mud drum, respectively, the gases flowing chamber and thence over the tubes connectingsaid steam and water drum to said mud drum,vthe tubes yof said lower bank through which the gases iow being arranged one i above the other. Y Y* Y v l 19. In a steam boiler, an upper steam andY water drum, a lower` mud drum, tubes connecting said steam and water drum and said mud drum, a furnace, a supplemental circulatory system comprising an upper and a lower bank of tubes located in advance of said first mentioned tubes with respect to the How of gases and connected at one end to a common water chamber and extending in dierent directions to form a secondary combustion chamber, the other ends of the tubes e of fsaid banks being connected at their other ends to said steam and water drum and to said mud drum, respectively, the gases flowing from said furnace over the tubes ofone ofsaid banks into Said secondary combustion chamber and thenceover thetubes connectingsaidsteam and water drum to said mud drum, and a roof baille disposed above the lower bank -of tubes wall for directing the gases tosaid secondaryV BOT' and extending forwardly from the furnace combustion chamber, the tubes of said lower bank being exposed for substantially their entire length of the radiant heat of the furnace.

20. In a steam boiler, an upper steam and Water drum, a lower mud drum, tubes connecting said steam and water drum and said mudV drum, a supplemental circulatory system comprlsingan upper and a lower bank of tubes Alocated in advance. of said irstmentioned tubes with respect to the flow of gases and connected at one end to a common water cham- Y ber and extending in dierent directions to form a secondary combustion chamber,fother drums to which the opposite ends of the tubes of said banks are connected, and connections between said last mentioned drums and the steam and water drum and mud drum, re-

spectively.

' DAVID S. JACOBUS.

zo: y 

